title: Return of spontaneous circulation with a compression:ventilation ratio of 15:2 versus 3:1 in newborn pigs with cardiac arrest due to asphyxia.
abstract: OBJECTIVE
  International guidelines recommend a compression to ventilation (C:V) ratio of 3:1 in neonates, and 15:2 for other paediatric age groups. The authors aimed to compare these two C:V ratios in a neonatal swine model of cardiac arrest following asphyxia.
  
  
  METHODS
  Experimental animal study.
  
  
  METHODS
  Facility for animal research.
  
  
  METHODS
  22 newborn pigs (age 12-36 h, weight 2.0-2.7 kg).
  
  
  METHODS
  Progressive asphyxia until asystole. Animals were randomised to receive C:V 3:1 (n=11) or 15:2 (n=11).
  
  
  METHODS
  Return of spontaneous circulation (ROSC) was defined as a heart rate ≥ 100 bpm. Also of interest were haemodynamic parameters, cerebral and systemic oxygen saturation and the proinflammatory cytokine interleukin-1β (IL-1β).
  
  
  RESULTS
  Two animals in each group did not achieve ROSC. Mean (SD) increase in diastolic blood pressure (DBP; mm Hg) during compression cycles was significantly higher at a C:V ratio of 15:2 than 3:1 (7.1 (2.8) vs 4.8 (2.6)). Median time (IQR) to ROSC for the 3:1 group was 150 (140-180) s, and 195 (145-358) s for the 15:2 group. There were no significant differences in the temporal changes in haemodynamic parameters or oxygen saturation indices between the groups. IL-1β levels in cerebrospinal and bronchoalveolar lavage fluid was comparable between the groups.
  
  
  CONCLUSIONS
  In neonatal pigs with asphyxia-induced cardiac arrest, the response to a C:V ratio of 15:2 is not better than the response to a C:V ratio of 3:1 despite better generation of DBP during resuscitation.
authors.affiliation: Department of Paediatrics, Akershus University Hospital, 1478 Lørenskog and Department of Paediatric Research, Oslo University Hospital, Rikshospitalet, 0027 Oslo, Norway. a.l.solevag@medisin.uio.no
authors.forename: Anne L
authors.initials: AL
authors.lastname: Solevåg
authors.forename: Ingrid
authors.initials: I
authors.lastname: Dannevig
authors.forename: Myra
authors.initials: M
authors.lastname: Wyckoff
authors.forename: Ola D
authors.initials: OD
authors.lastname: Saugstad
authors.forename: Britt
authors.initials: B
authors.lastname: Nakstad
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D001237:Asphyxia / Q000150:complications*; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D004195:Disease Models, Animal; D005260:Female; D006323:Heart Arrest / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D006336:Heart Massage / Q000379:methods; D006439:Hemodynamics / Q000502:physiology; D008297:Male; D012121:Respiration, Artificial / Q000379:methods; D034421:Sus scrofa; D016896:Treatment Outcome